User-agent: *
Allow: /
Disallow: /wp-admin/
Disallow: /wp-includes/
Disallow: /wp-content/uploads/
Disallow: /wp-content/uploads/woocommerce_uploads/2016/11/Dr.-John-Rusins-FHT-Program.pdf
Disallow: /pdfs/ # Block the /pdfs/directory.
Disallow: *.pdf$  # Block pdf files from all bots. Albeit non-standard, it works for major search engines.